Statement of the Technical Field
The technical field of this disclosure comprises earth orbiting satellites, and more particularly concerns methods and systems for tracking earth orbiting satellite equipment and services.
Description of the Related Art
Operational control of space orbiting satellites requires knowledge of their position and velocity. Likewise, delivery of satellite services require that equipment managers are able to track and control the position, velocity and orbit of satellites in Earth orbit. Further, accurate and up-to-date information concerning satellite position and velocity is important to prevent collisions. As the number of satellites in orbit grows, the potential for collision between satellites increases. Many new satellite assets compound congestion to the already crowded area surrounding Earth.
Systems for tracking satellites have traditionally used visual, radar and optical methods. These methods can be employed using ground locations as well as using airborne and space-borne platforms. Ground tracking methods require large and complex installations including high prime power and massive structures for stable operation. Airborne and space-borne operation involve complex tracking mechanisms and onboard two-way communications.
The U.S. Strategic Command (USSTRATCOM), through its Joint Space Operations Center (JSpOC) is tasked with tracking all artificial objects in Earth orbit. But tracking limitations exist since the majority of JSpOC space tracking radars are located in the Northern Hemisphere. Accordingly, JSpOC relies on this tracking radar information as well as data provided from the satellite owner/operators to consistently track the location and velocity of such satellites.
There is a rapidly growing interest in small low-cost satellite systems in Low Earth orbit (LEO) and to a lesser extent Medium Earth orbit (MEO) and Geosynchronous orbit (GEO). A Low Earth orbit is any orbit below 2,000 km. A Medium Earth orbit is defined as any orbit between 2,000 and 35,786 km. A geosynchronous orbit is an orbit with an altitude of 35,786 kilometers.
Nanosatellites are small satellites which are often used for research. CubeSats are a type of nanosatellites which are relatively small in size (e.g., 10 cm×10 cm×10 cm) and commonly weigh less than 1.33 kg. The CubeSat Launch Initiative (CSLI) organized by the National Aeronautics And Space Administration (NASA) provides access to space for CubeSats, developed by the NASA Centers and programs, educational institutions and non-profit organizations. This program offers CubeSat developers access to a low-cost pathway to conduct research in the areas of science, exploration, technology development, education or operations.